AIPS HELP file for ISPEC in 31DEC21
As of Wed May 5 15:55:23 2021
ISPEC: Task to plot spectrum of a specified portion of an image
USERID -32000.0 32000.0 User ID. ignored
INNAME Image name (name)
INCLASS Image name (class)
INSEQ 0.0 9999.0 Image name (seq. #)
INDISK 0.0 9.0 Disk drive #
BLC 0.0 4096.0 Bottom left corner of image
TRC 0.0 4096.0 Top right corner of image
NBOXES 0.0 50.0 Number of boxes in CLBOX
CLBOX Windows to use
DOINVERS -1.0 1.0 Do operation outside windows
OPTYPE 'FLUX','LGFL','LNFL', 'FDER'
PIXRANGE Range of intensities to plot
ZINC -8192.0 8192.0 Increment on freq axis.
< 0 => invert Z axis in plot
SMOOTH Frequency smoothing function
LTYPE -410.0 410.0 Type of labeling: 1 border,
2 no ticks, 3 standard, 4 rel
to center, 5 rel to subim cen
6 pixels, 7-10 as 3-6 with
only tick labels
<0 -> no date/time
DOCENTER -1.0 1.0 > 0 => plot with box-like
lines, else plot line to
DOTV -1.0 1.0 > 0 Do plot on the TV, else
make a plot file
GRCHAN 0.0 8.0 Graphics channel 0 => 1.
DOPRINT -3.0 132.0 > 0 => use the terminal, 0 =>
no output, < 0 => printer or
file, > 72 => terminal width
Printer disk file to save
DOSLICE -1.0 2.0 > 0 => save as SLice file
XYRATIO 0.0 Stretch the X axis wrt Y axis
0 -> 1.33
FACTOR Scale xDER plots; 0 -> 1
Use : Task to plot and print the average brightness or flux of an area
in the first two axes of an image as a function of location on the
third axis of an image. For example, this is a quick way to
display a single spectrum per point or area and avoids the use of
TRANS. The user can determine the area for which he wishes to
know the spectrum by using the verb TVWIN followed by GO ISPEC.
The spectrum will be placed in a plot file and can be displayed
with the display task of the user's choice. To obtain spectra for
each pixel over a given area the user should use TRANS and PLCUB.
Note that the third axis does not have to be a spectral-line axis
- all standard axis types are allowed. (If the first 2 axes are
not celestial coordinates, then the conversion from Jy/beam to Jy
for OPTYPE 'FLUX' cannot be done, however.)
If the third axis is FQID, the plots made will be adjusted to a
frequency axis with points placed appropriately. Slices made
will be interpolated onto a regular frequency grid.
For plots over irregular regions, specified using a "botch"
image, see task BLSUM.
USERID......User ID of owner of image. Ignored.
INNAME......Image name(name). blank => any
INCLASS.....Image name(class). blank => any
INSEQ.......Image name(seq. #). 0 => any
INDISK......Disk drive # of image. 0 => any
BLC.........The Bottom Left-hand pixel of the subarray of the image to
be plotted. The value (0,0,...) means (1,1,1,1,1,1,1).
TRC.........The Top Right-hand pixel of the subarray of the image to
be plotted. The value (0,0,...) means the top right hand
corner of the entire image.
NBOXES......<= 0 compute over BLC to TRC
> 0 use the windows in CLBOX for the first 2 axes
CLBOX.......Areas in the first two axes over which to compute the
spectrum. Up to 50 may be specified. An area is either
rectangular from CLBOX(1,i) to CLBOX(3.i} in X and
CLBOX(2,i) to CLBOX(4,i) in Y or it is circular indicated
by CLBOX(1,i) < 0 with CLBOX(2,i) the radius and
CLBOX(3,i) the center in X and CLBOX(4,i) the center in Y.
Boxes may overlap, a pixel will be counted only once.
DOINVERS....> 0 => do the operation outside the BLC/TRC or NBOXES
<= 0 => do inside those region(s).
OPTYPE......'FLUX' => plot and print the sum of the valid intensities
in the subarray, converted to Jy from Jy/beam
in Clean images.
'LGFL' => like FLUX but vertical scale in log base 10
'LNFL' => like FLUX but vertical scale in log base e
'AVER' => plot and print the average intensity.
'LGAV' => like AVER but vertical scale in log base 10
'LNAV' => like AVER but vertical scale in log base e
'FDER' => like FLUX but output is derivative out(i) =
(flux(i+1)-flux(i)) * FACTOR
'ADER' => like AVER but output is derivative out(i) =
(aver(i+1)-aver(i)) * FACTOR
'XLGF' => like LGFL but both axes in log base 10
'XLGA' => like LGAV but both axes in log base 10
otherwise => AVER
PIXRANGE....Range of pixel values to plot; values below PIXR(1) are
set to PIXR(1), values above PIXR(2) are set to PIXR(2).
PIXR(1) >= PIXR(2) implies use the full range of pixel
values in the image.
ZINC........Increment between plotted pixels on 3rd axis.
If < 0, abs(ZINC) is used and the Z axis is inverted
when listing and plotting.
SMOOTH......Specifies the type of spectral smoothing to be applied to
a uv database . The default is not to apply any smoothing.
The elements of SMOOTH are as follows:
SMOOTH(1) = type of smoothing to apply: 0 => no smoothing
1 => Hanning, 2 => Gaussian, 3 => Boxcar, 4 => Sinc
5 => Hanning, 6 => Gaussian, 7 => Boxcar, 8 => Sinc
SMOOTH(2) = the "diameter" of the function, i.e. width
between first nulls of Hanning triangle and sinc
function, FWHM of Gaussian, width of Boxcar. Defaults
(if < 0.1) are 4, 2, 2 and 3 channels for SMOOTH(1) =
1 - 4 and 5 - 8, resp.
SMOOTH(3) = the diameter over which the convolving
function has value - in channels. Defaults: 1,3,1,4
times SMOOTH(2) used when input SMOOTH(3) < net
Hanning, Gaussian, and Sinc functions are always
symmetric. Boxcar allows only integer widths and has value
1.0 in all included channels. If the integer is odd, the
function is symmetric. If it is even, the function is
asymmetric having one more channel included to the
"right". Thus width 2 averages channels 1 and 2 in output
channel 1. Width 4 averages channels 1 through 4 in
output channel 2. The frequency reference pixel is
suitably adjusted in such cases. This is a change from
symmetric boxcars made in March 2021.
NOTE: smoothing is not recommended in Frequency ID axes.
LTYPE.......Labelling type, see HELP LTYPE for details:
1 = border, 2 = no ticks, 3 or 7 = standard, 4 or 8 =
relative to ref. pixel, 5 or 9 = relative to subimage
(BLC, TRC) center, 6 or 10 = pixels. 7-10 all labels
other than tick numbers and axis type are omitted.
Less than 0 is the same except that the plot file
version number and create time are omitted.
Add n * 100 to alter the metric scaling.
DOCENTER....False (<= 0) means to draw plot lines between the data
points of the "spectrum" producing a jagged looking plot.
True (> 0) means to plot 1-channel horizontal lines
centered on each data point and connected to adjacent
points by vertical lines producing a histogram-like plot.
DOTV........> 0 => plot directly on the TV device, otherwise make a
plot file for later display on one or more devices
(including the TV if desired).
GRCHAN......Graphics channel (1 - 7) to use for line drawing. 0 => 1.
DOPRINT.....False (<= 0) use the line printer if OUTPRINT = ' '
else write named OUTPRINT file only.
When OUTPRINT is not blank, DOPRINT=-2 suppresses the
page-feed character on page headers and DOPRINT=-3
suppresses page headers and most other header
information. When OUTPRINT is blank, the line
printer will be used. ISPEC now counts the lines
to be printed before printing any and asks for
permission to continue if the count > 500.
True (> 0) use the terminal interactively. The task will
use the actual terminal width as a display limit
unless 72 < DOPRINT < width. In that case, the display
limit will be DOPRINT characters.
OUTPRINT....Disk file name in which to save the line printer output.
' ' => use scratch and print immediately for interactive
jobs - batch jobs use OUTPRINT = 'PRTFIL:BATCHjjj.nnn'
(jjj= job #, nnn = user #). When OUTPRINT is not blank,
multiple outputs are concatenated, and the file is not
DOSLICE.....> 0 => save the spectrum as a SLice file suitable for
the usual plotting and fitting done on slices.
XYRATIO.....The ratio of the axes X to Y in the plot. 1.0 makes a
square plot. 0 -> 1.3 (about the usual ratio of X to Y
on the TV screen or A format paper).
FACTOR......Scale factor for ADER and FDER plots only; 0.0 -> 1.0.
Used to adjust units from Jy/channel to Jy/(km/s) or
other things as needed. Can reverse sign.